MS3 Basic burble-pop on lift
#1
Senior Member
Thread Starter
iTrader: (5)
Join Date: Nov 2013
Location: Wisconsin
Posts: 655
Total Cats: 70
MS3 Basic burble-pop on lift
So my MS2E turned off the injectors when I was lifted and coasting. Cool.
My brand new MS3 does the same thing, except that after they turn off, it goes full lean, and then all of the sudden my WBO2 shows like 11 for a split second, I get a burble and/or pop, then it goes full lean again.
I heard on top gear that a car mfg was doing this (BMW i believe?) by design to get that pop, just wondering if this is normal for the MS.
My MS2 would burble sometimes, just from pulling fuel off the cylinder walls, but it never registered on the WB which is what has me confused. This time around it's happening long enough to register on the wideband _every time_ i lift. Googling gets me a lot of people saying to pull timing. I don't think that's it.
MS3 built by rev
almost completely basemap (ran VEAL for a while today)
3" catless midpipe built by 18psi (?)
3" enthuza XR turbo
GT2554R
460cc injectors
PS: Assuming there's nothing wrong, and this is fine to be happening/by design, I love it love it love it.
My brand new MS3 does the same thing, except that after they turn off, it goes full lean, and then all of the sudden my WBO2 shows like 11 for a split second, I get a burble and/or pop, then it goes full lean again.
I heard on top gear that a car mfg was doing this (BMW i believe?) by design to get that pop, just wondering if this is normal for the MS.
My MS2 would burble sometimes, just from pulling fuel off the cylinder walls, but it never registered on the WB which is what has me confused. This time around it's happening long enough to register on the wideband _every time_ i lift. Googling gets me a lot of people saying to pull timing. I don't think that's it.
MS3 built by rev
almost completely basemap (ran VEAL for a while today)
3" catless midpipe built by 18psi (?)
3" enthuza XR turbo
GT2554R
460cc injectors
PS: Assuming there's nothing wrong, and this is fine to be happening/by design, I love it love it love it.
#3
I noticed the same behaviour when I swapped to MS3 from the DIYPNP, on the MS2/DIYPNP the overrun fuelcut activates and the AFR immediately goes to fuel lean and stays there, with the MS3 and the exact same settings it's like Mlev described - fuelcut activates - AFR goes full lean - swings back to full rich for a split second - goes full lean again.
This is with AE only (no EAE - never git around tuning that), the same settings for decel fuel amount etc.
I noticed that some years ago, when I swapped to MS3, but never cared to look deeper into it.
This is with AE only (no EAE - never git around tuning that), the same settings for decel fuel amount etc.
I noticed that some years ago, when I swapped to MS3, but never cared to look deeper into it.
#4
Elite Member
iTrader: (1)
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,642
Total Cats: 42
If you like the burbles/pops then intentionally tune the overrun areas to be lean i.e. 15:1 or leaner, you also want to really retard the timing in the same area.
If you like obnoxious bangs, then tune the area to be stupid rich (9:1+)
If you like obnoxious bangs, then tune the area to be stupid rich (9:1+)
#9
Elite Member
iTrader: (1)
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,642
Total Cats: 42
MS3 (depending on firmware version obviously) has a 'softer' entry into ORFC, IIRC it cuts individual cylinders and leans them out rather than cutting the lot all at once.
Would probably explain the extra air in the exhaust causing the pops/burbles (pushed though from the 'cut' cylinders).
Would probably explain the extra air in the exhaust causing the pops/burbles (pushed though from the 'cut' cylinders).
#11
Senior Member
Thread Starter
iTrader: (5)
Join Date: Nov 2013
Location: Wisconsin
Posts: 655
Total Cats: 70
It just seems weird to me that it knows to cut, and then it comes back in, and then it cuts again. But there's no lurch at all when it happens, like there is when you're kinda riding the RPM limit of the fuel cut.
Also had a weird rubbing/buzzing sound coming from under the car, but it seemed like it was only under load. Not sure if it's a small exhaust leak out that stupid *** slip-joint-clamp thing on the DP or what, but it was very hard to hear clearly as my new exhaust is slightly on the loud side under load now.
Just as long as it's a rubbing from under the car and not my compressor wheel rubbbing again... ><
Need to climb under her again today, poke around a bit, and then get back to tuning. Woo!
Also had a weird rubbing/buzzing sound coming from under the car, but it seemed like it was only under load. Not sure if it's a small exhaust leak out that stupid *** slip-joint-clamp thing on the DP or what, but it was very hard to hear clearly as my new exhaust is slightly on the loud side under load now.
Just as long as it's a rubbing from under the car and not my compressor wheel rubbbing again... ><
Need to climb under her again today, poke around a bit, and then get back to tuning. Woo!
#13
Senior Member
Thread Starter
iTrader: (5)
Join Date: Nov 2013
Location: Wisconsin
Posts: 655
Total Cats: 70
Not sure. I got the car running and coolant burped and timing set and all that at 11pm and had to work at 6am, I literally just drove it around a 1/4 mile loop and noticed that it was doing the stuff in the OP every single time I lifted, and figured I'd ask since my MS2 didn't do it.
I don't have my MS2E anymore, but I should be able to dig into the old MSQs and check it out. I'll do that after work.
To be clear, this is not when I hit the limiter, this is when I'm cruising at 3k RPM and then lift. Pretty sure we're all on the same page there, just want to make sure.
I don't have my MS2E anymore, but I should be able to dig into the old MSQs and check it out. I'll do that after work.
To be clear, this is not when I hit the limiter, this is when I'm cruising at 3k RPM and then lift. Pretty sure we're all on the same page there, just want to make sure.
#15
There is a delay before overrun cut-off kicks in. Maybe thats it. To fix it, possibly lower the delay and auto-tune the very bottom row of fuel map.
I have overrun enabled after 1-2 seconds and overrun row is static 10* timing. The 10* pleases my inner ricer. If you set the bottom row timing to not retard like that, then it won't make any noises.
I have overrun enabled after 1-2 seconds and overrun row is static 10* timing. The 10* pleases my inner ricer. If you set the bottom row timing to not retard like that, then it won't make any noises.
#16
Retired Mech Design Engr
iTrader: (3)
Join Date: Jan 2013
Location: Seneca, SC
Posts: 5,009
Total Cats: 856
Was wondering the same thing. Didn't have enough experience to know if the readings were real or some sort of artifact. Mine have no burbling, just the lean / rich / lean thing. I will look into the anti lag. I kept thinking I needed more worke on the low kPa rows of the VE table, but it is good on steady state
#17
Was wondering the same thing. Didn't have enough experience to know if the readings were real or some sort of artifact. Mine have no burbling, just the lean / rich / lean thing. I will look into the anti lag. I kept thinking I needed more worke on the low kPa rows of the VE table, but it is good on steady state
Anti-lag cuts spark, retards timing, and sends unspent fuel in the exhaust, and it ignites when it hits the manifold, causing backpressure, and allowing the turbo to stay spooled when you aren't accelerating. This creates LOUD burples pops and bangs, like what you'd hear from rally cars.
#18
Senior Member
Thread Starter
iTrader: (5)
Join Date: Nov 2013
Location: Wisconsin
Posts: 655
Total Cats: 70
The anti-lag reference was a joke, don't actually go playing with those settings (I mean, unless you want to...)
Anti-lag cuts spark, retards timing, and sends unspent fuel in the exhaust, and it ignites when it hits the manifold, causing backpressure, and allowing the turbo to stay spooled when you aren't accelerating. This creates LOUD burples pops and bangs, like what you'd hear from rally cars.
Anti-lag cuts spark, retards timing, and sends unspent fuel in the exhaust, and it ignites when it hits the manifold, causing backpressure, and allowing the turbo to stay spooled when you aren't accelerating. This creates LOUD burples pops and bangs, like what you'd hear from rally cars.
There's a group of ricers that meet every friday and saturday night, and I kinda want to drive out there and do a two-step just to see their faces.